Importance The programmed death 1 (PD-1) pathway limits immune responses to
melanoma and can be blocked with the humanized anti-PD-1 monoclonal antibody
pembrolizumab. Objective To characterize the association of pembrolizumab with tumor
response and overall survival among patients with advanced melanoma. Design, Settings,
and Participants Open-label, multicohort, phase 1b clinical trials (enrollment, December
2011-September 2013). Median duration of follow-up was 21 months. The study was …